Article Aegean Trees and Timbers: Dendrochronological Survey of the Island of Symi Anastasia Christopoulou 1,* , Barbara Gmi ´nska-Nowak 1, Yasemin Özarslan 2 and Tomasz Wa˙zny 1 1 Centre for Research and Conservation of Cultural Heritage, Faculty of Fine Arts, Nicolaus Copernicus University, 87-100 Toru´n,Poland; [email protected] (B.G.-N.); [email protected] (T.W.) 2 Department of Archaeology and History of Art, Koç University, 34450 Istanbul, Turkey; [email protected] * Correspondence: [email protected] Received: 15 October 2020; Accepted: 25 November 2020; Published: 27 November 2020 Abstract: The current study presents the results of the first dendrochronological survey performed over the East Aegean island of Symi. Research Highlights: Dendrochronological research of the East Aegean region is of paramount importance since dendrochronological data from the region, and especially the islands, are still limited. Background and Objectives: The main aim of the study is to explore the dendrochronological potential of the island, focusing on the dating of historical wood and buildings as well as dendroprovenancing. Materials and Methods: A total of 57 wood samples were collected from historical timber from windmills and architectural elements, including doors and warehouse planks, while 68 cores were collected from the three dominant tree species of the island—Cupressus sempervirens, Pinus brutia, and Quercus ithaburensis subsp. macrolepis—in an attempt to develop local reference chronologies that could be useful in dating historical timber Results: Of the historical timber, at least nine different species have been detected, with conifers representing the majority of the collected material. In total, 56% of the dendroarchaeological samples, belonging to four different species, were dated absolutely. According to cross-dating and dendroprovenancing results, Pinus nigra, Cedrus sp., and Quercus sp. represent timber imported from present-day Turkey while the fir samples collected from the windmills originate from Central Europe. The use of local timber is also highly probable although it could not be confirmed by the reference chronologies developed for the three dominant tree species of the island. Conclusions: The results of the study reveal the dendrochronological potential of the island from both dendroarchaeological and dendroecological perspectives. The finding that most of the wood was imported mainly from Turkey highlights the importance of timber trade with the Turkish mainland during the mid-18th and 19th centuries. Chronologies developed from living trees could be used in future studies for dating historical material while further research would increase our understanding of past timber trade and the island’s history. Keywords: dendroarchaeology; tree-rings; cypress; Turkish pine; valonia oak; conifers; timber; trade 1. Introduction A dendrochronological survey of the Aegean islands is of paramount importance since, up to now and according to our current knowledge, dendrochronological data from the region are limited to Crete [1–6], Samos [7,8], and Euboea [9,10]. The majority of these studies focus on living trees and the environmental and/or climatic factors that drive their growth trend and survival [1–5,7–9]. Only two of these studies deal with dendroarchaeological studies of historical buildings from the Venetian and Ottoman periods [6,10]. There are plenty of reasons why the inland part of Greece has been overlooked compared to the mainland with regard to living trees. The main reason is the lower suitability of tree species for dendrochronology and the expected limited availability of older trees, compared to the Forests 2020, 11, 1266; doi:10.3390/f11121266 www.mdpi.com/journal/forests Forests 2020, 11, 1266 2 of 15 higher mountains of continental Greece, as trees of lower altitudes are more exposed and prone to human activities, and therefore they rarely reach really old ages. Nonetheless, the presence of old trees on the Aegean islands cannot be ruled out, especially on islands where species such as Cupressus sempervirens, Pinus brutia and Quercus ithaburensis subsp. macrolepis are still present. In terms of historical timber, dendrochronology has been mainly limited to northern Greece [11,12] where the available timber was more abundant and easier to handle. Nonetheless, recent studies highlight the potential of several historical buildings such as monasteries, churches, and mansions, where timber is available in Southern Greece and the islands [13]. The current study presents the results of the first dendrochronological survey performed on the island of Symi, an East Aegean island. We initiated our dendrochronological survey after a request to date a group of standing windmills located on a hill to the east of Ano Symi (Figure1). Our first visits to the island revealed its dendrochronological potential not only from a dendroarchaeological perspective, but also for dendroecological and future climate reconstruction studies, due to the presence of old-looking forest stands and woodlands. The main objective of our study was to perform the first dendrochronological survey of the island, focusing on dating of historical timber and dendroprovenancing. To identify and date locally sourced timber which may have been utilized in local buildings and carpentry, cores from living trees were collected to develop local tree-ring chronologies. Such local chronologies are essential for the ongoing development of an eastern Mediterranean master chronology since the only continuous tree-ring chronology available for the region going back to 1089 AD has been developed from material originating from only Turkey and mainland Greece [14]. However, the material used for that master chronology contains also wood imported from the Balkans [15]. Therefore, the development of local chronologies from any part of the eastern Aegean region could proveForests beneficial 2020, 11, x FOR for PEER di REVIEWfferent disciplines and regional projects. 3 of 16 Figure 1. Location ofFigure the 1. studyLocation of area the study and area the and di theff differenterent study study sitessites where samples where were samples collected from were collected from historical timber (red dots) and living trees (green dots): (1) windmills, (2) doors and imported timber, historical timber (red(3) dots)valonia oak and woodland, living (4) trees Cypress (green forest, and dots): (5) Turkish (1) pine windmills, forest. (2) doors and imported timber, (3) valonia oak woodland, (4) Cypress forest, and (5) Turkish pine forest. 2. Materials and Methods 2.1. Study Area, Study Sites, Study Material, and Sample Collection Symi is a Greek island, geographically belonging to the Dodecanese island chain, located about 41 kilometres N-NW of Rhodes, while the nearest mainland is made up of the Datça and Bozburun peninsulas of Muğla province of Turkey. The island is mostly mountainous and rocky, and its highest elevation (Vigla peak) is 616 m. The Municipality of Symi covers the neighbouring uninhabited offshore islets with a total land area of 65,754 km2 [16]. The climate of the island is semi-arid Mediterranean, with short, mild and wet winters, followed by long, hot and dry summers [17]. The economy of Symi was traditionally based on shipbuilding and sponge industries [18] and the island Forests 2020, 11, 1266 3 of 15 2. Materials and Methods 2.1. Study Area, Study Sites, Study Material, and Sample Collection Symi is a Greek island, geographically belonging to the Dodecanese island chain, located about 41 kilometres N-NW of Rhodes, while the nearest mainland is made up of the Datça and Bozburun peninsulas of Mu˘glaprovince of Turkey. The island is mostly mountainous and rocky, and its highest elevation (Vigla peak) is 616 m. The Municipality of Symi covers the neighbouring uninhabited offshore islets with a total land area of 65,754 km2 [16]. The climate of the island is semi-arid Mediterranean, with short, mild and wet winters, followed by long, hot and dry summers [17]. The economy of Symi was traditionally based on shipbuilding and sponge industries [18] and the island was particularly prosperous during the 19th century thanks to these two activities (Zographos, pers. com.). The island remained under the Ottoman rule from 1522 until 1912, but it was allowed to retain many of its privileges. Nowadays, the main source of income for the island is tourism, and the presence of tourists who regularly visit the islands is of particular interest from an anthropological point of view [19]. The vegetation of the island mainly consists of phrygana communities (low evergreen, shrub formation), remnants of pre-existing conifer woodlands dominated by cypress (Cupressus sempervirens L.) and Turkish pine (Pinus brutia Ten.), as well as sclerophyllous and deciduous forests [17]. Although Symi is one of the few islands where natural stands of Cypress can still be found [20], it is believed that cypress forests were wider in size in the past while, according to locals, most of the cypress trees today are younger than the end of the Ottoman period (1912 AD). In several parts of the island, especially in the north, valonia oak (Quercus ithaburensis subsp. macrolepis (Kotschy) Hedge and Yalt.) woodlands can be seen. Although Symi is not mentioned in the distributional and phytogeographical study of the taxon [21], both the areas where valonia oak woodlands are present and the understory vegetation are very similar to those described by Vrahnakis et al. [22]. Nevertheless, it is unclear whether these open woodlands are remnants of the once-existing wider natural forests or emerged as a result of large-scale cultivation, livestock grazing, and acorn production. 2.1.1. Historical Timber 1. The standing windmills The first study site was a group of six standing windmills located within a private land on a hill to the east of Ano Symi (Figure2). The owner of this land, the architect in charge of the ongoing renovation project as well as the Ephorate of Antiquities of Dodecanese responsible for Symi, wanted to know the age of these windmills. According to the architect, local timber was used in the construction of these six windmills.